[CLOSED PR] New gun addidtion to the "support" sec loadout

[virvatuli]

Not sure about this as it seems to be trying to push "Sec as a Medic" thing that we've been trying to avoid. It also basically renders the tranq rifle armoury spawns completely redundant. Halperidol darts are restricted to MDir, armoury, or HoS by nature of them being extremely powerful, and throwing them into a loadout is contrary to current balance.